The present invention concerns a packing for a product in powder form comprising a sophisticated locking device.
There is already a history of devices designed to issue a given quantity of caustic product and used for cleaning out lavatories.
Such a device for cleaning out lavatories is specifically described in Swiss Pat. No. 543 426.
The device described in this patent includes a lower housing fitted with a top cover and fitted in its lower part with notched slits, a collar being provided between the lower edge of the said housing and the cover. The device also comprises a lower housing which can slide in relation to the upper housing. It includes an initial upper cylindrical part, a second lower cylindrical part and an intermediate tapered part. In addition, the device comprises a tapered plug which is fixed to the lower part of the upper housing and which operates in conjunction with the lower housing during the locking of the device.
The function of this plug is to discharge the powder product in the upper housing. When the device is open, the powder product flows along the walls of the tapered plug which is then released from the lower container and the powder product passes through the slits of the upper housing.
The plug, with the tip of its taper pointed in the direction of of the upper housing, also includes a leg routed from the upper housing to the lower housing. This central leg has a double function. First, it makes it possible to position the device in the lavatory so that the device lies along the same axis as the letdown orifice of the lavatory. Additionally, it prevents any inadvertant opening of the device. In fact, as the leg protrudes slightly from the lower housing when the device is positioned on a continuous plane, when the user presses on the cover of the upper housing, the leg lying on the continuous plane prevents opening.
The device does not allow full locking. Although the leg prevents opening, i.e. the release of the upper and lower housings, when the use applies axial pressure, it does not allow correct locking when the user performs a rotation around the device's longitudinal axis. By such a rotation and a simultaneous push, the user is able to open this device.
The device disclosed in Swiss Pat. No. 543 426 presents a serious disadvantage since the powder product contained in the upper housing is generally a dangerous product whose basic ingredient is frequently caustic soda. A child who performs a push and simultaneous rotation may inadvertently open the device and get the powder product on its hands or on some other part of its body, and this may cause accidents.
The present aim of the invention is to overcome these disadvantages.